2016 was supposed to be the year of the modular phone—phones that allow add-ons, or ‘mods’, to be attached that give the device new or enhanced capabilities. That can mean powerful camera lenses, audio speakers or even image projectors that could easily be snapped onto a phone.

But the year came and went without notable success in the emerging field. Three major players entered the field, and only one is still pushing for modular phones.

Google announced Project Ara in early 2016 to explore modular phones, with an exterior that allowed multiple attachments to be added to the phone at the same time. The plan was shelved in September 2016, Reuters reported, in order to streamline Google’s hardware projects, which include the Google Pixel phone and Chromebook laptops.

In February 2016, LG launched G5, with mods that could be attached to the bottom of the phone, like a speaker or battery pack. To attach mods, users had to turn off the phone, remove the bottom of the phone (including the battery), and add the mod. The phone saw disappointing sales.

The only major player that’s still in the modular phone game is Motorola. The company is owned by Lenovo and its Moto Z Force smartphone series, which debuted in July 2016, has a magnetic surface on the back to which mods that appear like phone cases can be easily attached. It reached its benchmark of three million modular phone sales this year, according to company executives.

Lenovo’s senior vice president and chief marketing officer David Roman says the company is relying on profits from its well-established PC business so it can venture into developing smartphones as well as branching into artificial intelligence and data centers. He also noted that the company expects to break even in its smartphone division by the end of its fiscal year.

Motorola also just launched a 360-camera mod, two months after the release of the second generation of the Moto Z Force. The 360-camera costs $946, the same price as the Moto Z smartphone, and boasts 4K quality. We tried it out in advance of IFA 2017 in Berlin, and you can see the footage here. By comparison, the Samsung Gear 360 camera, a leader in the field, cost $229 at launch and features the same high resolution, but it cannot be attached to a phone.

Motorola’s mods fit onto the back of the phone like a phone case, and are attached using magnetic points on the phone. Pictured: The 360-camera mod.

The premise behind modular phones is that they are “future-proof.” Instead of buying a new phone every year to enhance the camera quality or battery life, users can just snap on the latest mod. But mods do not upgrade core features such as processing power or screen resolution.

Still, Motorola is aggressively moving towards modular phones, with mods like the JBL Soundboost 2, which acts like a speaker and gives the phone extra battery power to allow the user to play up to 10 hours of music. The GamePad mod turns a smartphone into a portable gaming console. Another, The Hasselblad Truezoom, gives the phone a 10x optical zoom and allows users to shoot raw footage, which is better for photo editing.

The mods are sleek and well-designed, making it easy to add new features to the phone. Still, the question remains: Do people really want modular phones?

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